Geological and Elemental Geochemical Characteristics of the Ore Vein No.1 in the Ciweigou Gold Deposit,Yanbian Area and their Exploration Significance

The Ciweigou gold deposit in the Yanbian area is typical of low sulphidation(LS) epithermal gold deposits in northeastern China. To determine the mineralization enrichment rules and deep exploration potential of this deposit,the ore vein No. 1,which has the highest industrial value in the ore area,is chosen as the study object. Based on previous work on ore-controlling conditions,gold mineralization and alteration characteristics,we analyze the geochemical characteristics of this deposit such as correlations of the metallogenic indicator elements,concentration zoning,and zoning sequence of elements combination. The results indicate that the ore veinNo. 1 occurs in the Mesozoic continental volcanic rocks,which is obviously controlled by NNE-trending transextensional faults in calderas. The chlorite alteration( often accompanied by carbonation) is considered to be an alteration sign of high grade ore blocks. The analysis of eleven trace elements in ores from different levels shows that only Hg and Ag have weak positive correlation with Au,while negative correlation are present between Au and other elements. Combining with the result of factor analysis,this work suggests,with the exception of Au,there is no other useful associated element. According to the vertical variation of metallogenic elements and element concentrations zonation,it can be concluded that the ore vein No. 1 in the Ciweigou gold deposit is featured by the segmented enrichment,with the mineralization concentrated at 220 ~ 260 m and 420 ~ 450 m levels.